1. Field of the Invention
This invention relates to the field of printed circuit board (PCB) test jacks, and particularly to test jacks for use on high-density PCBs.
2. Description of the Related Art
Printed circuit boards (PCBs) are often tested using a test probe which contacts a signal trace of interest. In some instances, test jacks are mounted onto the PCB to facilitate such testing. To provide signal and ground connections to the test probe, the test jack typically employs two or more through-hole pins that are inserted into through-holes on the PCB. These through-holes are bored all the way through the PCB, where they pass through signal and ground traces as necessary to effect a desired measurement. The through-hole pins of the test jack are soldered into their respective holes, thereby securing the jack to the PCB and providing the electrical connections.
However, when a PCB is a multi-layer board carrying a high-density of signal traces, each of the two or more through-holes required by the test jack can interfere with the routing of signals on the top and inner layers of the board. In addition, the many signal traces can force the through-holes to be located some distance away from their respective sources, which can adversely affect the quality of the probed signal.
The present test jack comprises a body portion arranged to interface with an external test probe, at least one surface mount conductor connected to the body portion and arrayed for attaching to corresponding surface pads on the surface of a PCB, and a signal conductor connected to the body portion. The signal conductor comprises a single through-hole pin for insertion into a corresponding single through-hole on the PCB. Using only a single through-hole pin reduces signal routing interference in the PCB when compared with a test jack employing multiple through-hole pins.
Alternatively, a test jack in accordance with the present invention may employ no through-hole pins. In this case, the signal conductor is also a surface mount-type, which is connected to the body portion and arrayed for attaching to a corresponding surface pad on the surface of a PCB.